Time not on Resilient Packet Ring's side

Time may be running out on an emerging standard for metropolitan Ethernet, as alternatives could beat it to market and close its window of opportunity.

As is usual in standards definition, the work on the IEEE 802.17 Resilient Packet Ring (RPR) is mired in political squabbling and the pursuit of proprietary interests and agendas. RPR is intended to optimize metropolitan ring topologies for packet transport with resiliency matching or exceeding SONET's.

But observers say RPR can ill-afford the infighting. The standard will take 18 months to fully bake, time enough for proprietary alternatives, including Cisco's Spatial Reuse Protocol (SRP), to fill the void.

That may be bad for businesses, because limited product choice for service providers means limited flexibility in negotiating equipment cost. If service providers have to pay more for equipment, they may charge more to provision the service that's based on it.

The RPR Alliance (RPRA) shrugs off the disagreements and says the standards work is on track.

"We have 90 companies involved with this standards effort," says Robert Love, chairman of the RPRA. "Everyone thinks their own flavor is best. Engineering issues and political issues encountered are normal in the early part of any standards process. From what I can see, though, we're still right on schedule with where we said we'd be."

While Love says there isn't one particular technology coming out head and shoulders above other proposals, there's a common agreement that Cisco's SRP technology, which defines transmission of IP over fiber rings, is the front-runner.

"Cisco has had a working technology for a number of years," says Ted Rado, former director of product marketing for Alidian Networks. "While they've had mixed success with it, they're the big gorilla here and the ones who are causing contention within the standards committee."

Cisco says the fact that it has had success with proprietary technologies is a plus.

"I think we bring an important advantage to the RPR effort," says Jeff Baher, senior manager of marketing for the metropolitan IP access group at Cisco. "We've been successful with our technology so far, and now we see there's a larger market there that we can address."

No competition?

The feeling within the RPRA and the 802.17 working group is that reports of RPR's struggle or eventual demise are coming from those who have the most to lose if RPR becomes a successful standard.

"The optical Ethernet guys are running scared," says Nigel Cole, vice president of business development at Corrigent Systems. "RPR is cheaper than optical Ethernet so there's propaganda going on in the market to make optical Ethernet look better."

The Metro Ethernet Forum disagrees.

"Our primary priority is to accelerate the adoption of Ethernet as the transport technology in the metropolitan-area network," says Nan Chen, forum president. "RPR is a different transport than Ethernet. We aren't even competing. We're defining something that can be deployed today, they're defining something that doesn't exist yet."

Current nonexistence could be RPR's biggest impediment, says David Dunphy, a Current Analysis analyst.

"Even the best solution might not succeed if it comes to market after a less compelling alternative that had better timing," Dunphy said in a recent report.

An Introduction to Resilient Packet Ring Technology
RPR Alliance white paper. In PDF.

RPR Alliance

Spatial Reuse Protocol
Cisco white paper.